The best thing about reviewing independent games is that, unlike commercial releases, you can often find some very unusual ideas. Big companies are terrified of unknowns and so release a constant stream of first person shooters, dull puzzle games and endless sequels.

I am pleased to say that 50 Castles is a rather bizarre puzzle game that would never fit the one-dimensional categories of most commercial ventures. Your aim is to build castles - fifty of them, naturally - by rotating and slotting pieces into gaps. Of course, you are under a strict time limit and things aren't quite so straightforward...

Firstly, you often have chickens to protect. Chickens are the favourite food of snakes, which can wander onto the screen and find a way into your castles for a free snack. If you have a cannon available, you can get your revenge... Try to save as many chickens as you can. As well as the potential loss of bonus points there are time penalties for having them eaten.

Later castles are also pestered by marauders, bearded men with bombs. Again, a cannon will soon get rid of them, but it's best to be quick about it as they like to blow up parts of your castle which then need replacing. As you can imagine, sometimes the screen gets rather hectic!

Graphics consist of a square grid - the size of which changes depending on the castle size. The early castles have huge blocks while later, bigger castles can be filled with tiny ones. Despite this variation in scale, the graphics remain clear and bright in all sizes. Snakes, marauders and chickens are cartoon in style, as is the game text.

Sound is... bizarre. The in-game music is pleasant and lively, suiting the frantic rate at which blocks need to be placed in order to keep within the time limit, and the sound effects are understandably minimal. All very normal. What makes the audial aspect of 50 Castles bizarre is the speech. Commentators with a range of regional accents spout inane phrases (or should that be 'insane phrases'?) whenever you do something special, such as take out a snake with a cannon. Commentators can be individually turned off...!

50 Castles is great fun but you soon grasp the central idea - place the blocks you are given into the correct holes. Aside from firing a cannon at a snake or marauder this is the only major aspect of the game, though one mean level tricked me by giving me a dud piece (which I had to discard). As such the game rapidly becomes a frantic race to build your castles within the time limit and you will soon be cursing your mouse for being too slow.

That said, this is a great game in many little ways - such as the axe symbols you can put in your name on the high score table. You can save your game before every level but get a score bonus if you don't. Indeed, bonuses are everywhere - as well as saving chickens and the ubiquitous time remaining bonus, there are coins spinning in some blank spots and hidden bonuses for many things. Place three blocks in two seconds for a time bonus, for instance. It is rather irritating in some ways too - for instance, it comes in a ZIP file rather than a proper installer, so you'll need to extract it manually.

Rusty Axe Games deserve credit for attempting something different and this is a game that defies description. To get a sense of how odd it truly is, one needs to play it. Just don't swear at the mouse too much. Or the chickens.